1. Field of the Invention
The present invention relates to a tape cartridge having a reel lock mechanism designed to stop reels from rotating when they are not in use. More particularly, the invention relates to a tape cartridge wherein the reel lock mechanism is released by a slider provided on the outer, lower face of the bottom wall of the cartridge casing.
2. Description of the Related Art
The existing art of this type of a conventional tape cartridge is typified by ones as disclosed in Japanese Patent Laid-Open Publications 287491/1987 and 241075/1989, as shown in FIGS. 16(A) through 16(C). These tape cartridges, designed for use in a DAT (digital audio tape) recorder, comprise a pair of reels 3, 3 rotatably arranged right and left inside a casing 1, where a tape 2 is to be wound around the reels 3, 3. In the front of the casing 1, there is formed a pocket 6 for use of tape loading, being opened at its front and lower portions. A front cover 7 is held to the casing 1 so as to be turnable and upwardly openable, serving to open and close the front face of the casing 1 and being normally urged into a closed position by a spring member.
A slider 9 is fitted to the outer, lower face of the bottom wall of the casing 1 so as to be slidable back and forth. The slider 9 closes the lower face of the pocket 6 in its forward advanced position, and opens the lower face of the pocket 6 in its backward retreated position.
Within the casing 1, there is provided a reel lock mechanism 60 designed to stop the right and left reels 3, 3 from rotating when they are not in use. The reel lock mechanism 60 has a plate-shaped reel lock member 61 which is located forward of the right and left reels 3, 3. The reel lock member 61 is slidable back and forth, and is urged by a spring member 67 to move backward. Further, right and left lock claws 62, 62 of the reel lock member 61 are extended backward so that the lock claws 62, 62 are mated with engaging teeth provided at the top forward ends of the reels 3, 3, thereby stopping the reels 3, 3 from rotating when they are not in use.
When the tape cartridge is loaded to the holder within the deck, the front cover 7 is opened upward by a cover-opening member on the deck side, as shown in FIG. 16 (C). Accompanying the upward opening action of the front cover 7, release protrusions 63, 63 provided on right and left side walls of the front cover 7 engage with release claws 65, 65 provided at end portions of right and left arms 64, 64 of the reel lock member 61, thereby causing the reel lock member 61 to be tractionally moved forward against the spring member 67 so that the reel lock is released.
The front cover 7 is a member which is in its closed position while the tape cartridge is out of use, and which covers the front, outer side of a tape 3 led out in the front of the casing 1. Therefore, in order that the front cover 7 is loaded to the casing 1 so as to be rotatable and openable/closable, it is necessary to rotationally urge the front cover 7 into its closed position by a spring member.
This being the case, in the conventional type for releasing the reel lock member 61 interlockingly with the upward opening action of the front cover 7, it is required not only to open the front cover 7 upward against the spring pressure of the spring member exclusively intended for this use, but also to simultaneously release the reel lock member 61 interlockingly with the front cover's opening action. Yet, to the reel lock member 61 is applied a spring force for holding the reel lock member 61 in such a position that the reel lock member 61 is in contact engagement with the reels 3, 3.
As a result, the conventional system increases the upward opening force of the front cover 7 by the member on the deck side. Accordingly, due to the reaction force of the upward opening force of the front cover 7, the front end portion of the tape cartridge is likely to be subjected to displacement or floating on the holder within the deck, which may result in an unstable running of the tape.
Further, due to an excessive cover-opening force applied to the front cover 7, the front cover 7 may be damaged at points where it is in contact with the cover-opening member on the deck side or where it is connected with the reel lock member 61.